WO2019202229A1

WO2019202229A1 - Assembly for electric motor of a motor vehicle

Info

Publication number: WO2019202229A1
Application number: PCT/FR2019/050762
Authority: WO
Inventors: Johan Kaes; Clémence KWACZEWSKI; Mickaia RABENJA; Ismaël FRANCO
Original assignee: Valeo Systemes Thermiques
Priority date: 2018-04-19
Filing date: 2019-04-02
Publication date: 2019-10-24
Also published as: FR3080504A1; FR3080504B1

Abstract

The invention relates to an assembly comprising a control module (2) for an electric motor of a motor-fan unit and a motor support (3) for housing said electric motor on which said control module (2) is mounted, the control module (2) including a printed circuit board (4) on which electronic components (5) are arranged as well as a radiator (6) thermally coupled with said printed circuit board (4), the assembly (1) comprising a vibrational uncoupling device (10) for uncoupling the assembly (1) from said electric motor, the vibrational uncoupling device (10) comprising at least one vibrational uncoupling pin (20) for fastening the radiator (6) and the printed circuit board (4) and/or the motor support (3).

Description

ELECTRIC MOTOR VEHICLE ELECTRIC MOTOR ASSEMBLY

The invention relates to the field of electric motors motor fan group, and an assembly comprising in particular a speed control module of an electric motor.

A motor vehicle is commonly equipped with a ventilation device, heating and / or air conditioning to regulate the temperature of a flow of air distributed to the interior of the passenger compartment of the vehicle.

The device generally comprises a housing delimited by partitions in which openings are provided, including at least one air inlet and at least one air outlet.

In known manner, the housing houses an air supply device (or air blower) for circulating the air flow from the air inlet to the air outlet. The housing also houses heat treatment means for heating and / or cooling the air flow prior to its distribution inside the passenger compartment.

Pulsers generally comprise electric motors, especially DC, switching with or without brush (also known under the name of "brushless"). These motors comprise a rotor and stator assembly, each of these components carrying electromagnetic elements whose interaction generates the displacement of the rotor relative to the stator.

An air blower for a heating, ventilation and / or air conditioning device for a motor vehicle, known to a person skilled in the art, comprises:

- an electric motor on which is mounted a paddle wheel;

an engine support in which said electric motor is housed;

said wheel adapted to generate an air flow in said heating, ventilation and / or air conditioning device;

- A control module of said electric motor, comprising a printed circuit board on which are mounted various electronic components.

The heating, ventilation and / or air conditioning device comprises a volute surrounding said wheel. The control module is mounted on the motor support of the air blower or on the volute of the heater, ventilation and / or air conditioning. The air flow used for the heating, ventilating and / or air conditioning thus allows the cooling of the control module.

A disadvantage of this state of the art is that the motor activity generates vibrations at a certain frequency, which may unfortunately coincide with a resonant frequency of the printed circuit board.

In this case, deformations may appear in the electronic components, which can damage them and also lead to the electrical disconnection of a power supply connector, or any other electrical component, often fixed on the printed circuit board .

In this context, the present invention aims to solve the aforementioned drawback.

For this, the invention proposes an assembly comprising a control module of an electric motor for a motor-fan unit and a motor support for housing said electric motor on which said control module is mounted, the control module comprising a card printed circuit board on which electronic components and a radiator in thermal coupling with said printed circuit board are arranged, the assembly comprising a vibratory decoupling device for decoupling the assembly from said electric motor, the vibratory decoupling device comprising at least one Vibration decoupling pin for fixing the radiator and the circuit board.

The assembly according to the present invention is protected from the vibrations generated by the electric motor thanks to the vibratory decoupling device, which also ensures the attachment of the elements of the assembly together.

According to another characteristic of the invention, said at least one pin is made of flexible plastic material, for example of the SEBS type.

According to another characteristic of the invention, said at least one pin comprises a rod for gripping the pin.

According to another characteristic of the invention, said at least one pin comprises comprising at least one shoulder for blocking the pin between the radiator and the printed circuit board and / or the motor support.

According to another characteristic of the invention, the assembly comprises an electrical connector provided with a ring, said at least one pin being configured to also fix said ring.

According to another characteristic of the invention, the radiator comprises an orifice of passage of said at least one pin and the printed circuit board comprises a passage opening of said at least one pin, the passage of the radiator being arranged opposite the passage opening of the printed circuit board.

According to another characteristic of the invention, the vibratory decoupling device comprises a layer of flexible material disposed between the engine support and the radiator.

The subject of the invention is also a method of manufacturing an assembly comprising a control module for an electric motor of fan motor group and a motor support for housing said electric motor on which said control module is mounted, the module of control comprising a printed circuit board on which are disposed electronic components and a radiator in thermal coupling with said printed circuit board, the assembly comprising a vibrating decoupling device for decoupling the assembly of said electric motor, the method comprising a step positioning at least one vibratory decoupling pin between the radiator and the printed circuit board and / or the motor support so as to fix the radiator and the printed circuit board and / or the motor support.

According to another characteristic of the invention, said at least one pin comprising a gripping rod and at least one locking shoulder, the positioning step comprising a step of forcing said at least one pin into the card and into the card. the radiator and / or the engine support and a withdrawal step during which the gripping rod is pulled in a direction opposite to the insertion direction so as to position the pin, each shoulder now blocking the pin in position.

According to another characteristic of the invention, the method comprises a preliminary overmolding step where the pin, here in SEBS, is directly overmolded on the engine support, in other words, the pin is created during the overmoulding stage, in other words it is the SEBS injection step that creates the pawn during this overmolding step.

According to another characteristic of the invention, the method comprises a preliminary overmolding step during which the motor support is overmolded with a layer of flexible material and said at least one peg. Embodiments of the invention given by way of nonlimiting examples and with reference to the appended figures in which:

- Figure 1 is a perspective view of an assembly according to the present invention, a pin not being shown;

- Figure 2 is a perspective view of the assembly of Figure 1, several pins being shown;

- Figure 3 is a schematic front view of a pin for all of Figures 1 and 2 according to a first embodiment;

- Figure 4 is a schematic front view of a pin for all of Figures 1 and 2 according to a second embodiment;

- Figure 5 is a front view of a pin for all of Figures 1 and 2 according to a third embodiment; and

- Figure 6 is a schematic view of possible positioning of the pins of Figures 3 to 5.

FIG. 1 illustrates a perspective view of an assembly 1 according to the present invention for an air blower, for example a ventilation, heating and / or air-conditioning device for a motor vehicle.

The air blower comprises an electric motor, not shown, preferably of the DC type.

As illustrated in FIG. 1, the assembly 1 comprises a control module 2 for the electric motor.

The assembly 1 also comprises a motor support 3 for housing the electric motor and on which the control module 2 is mounted.

As is also apparent from FIG. 1, the control module 2 comprises a printed circuit board 4 on which electronic components 5 are arranged.

The control module 2 also comprises a heat sink, also called radiator, 6, in thermal coupling with the printed circuit board 4.

The radiator 6 makes it possible in particular to dissipate the heat produced by the electronic components 5.

In the illustrated embodiments, the card 4 has the general shape of a disk provided with a central orifice 7.

Likewise, in the illustrated embodiments, the radiator 6 presents a general disc shape with a central orifice 8.

Of course, the invention is not limited to a specific geometry of the card 4 or the radiator 6.

As is also apparent from the figures, the card 4 is provided with holes 9 for passing pins of a vibratory decoupling device 10 detailed later.

The radiator 6 is also provided with holes 11 for passing pions detailed later.

Each hole 9 is arranged opposite an associated hole 11.

As can be seen in FIG. 2, the blower comprises an electrical connector 12 configured to power the card 4 electrically.

The connector 12 is offset from the card 4 and is connected to the card 4 by cables.

The connector 12 comprises a ring 13, detailed later.

Vibration decoupling device

As already indicated, the assembly 1 comprises a vibratory decoupling device 10 for decoupling the assembly 1 from the electric motor, which makes it possible to prevent the vibrations generated by the motor from propagating to the electronic components 5 carried by the power supply card. printed circuit board 4.

The vibrating decoupling device 10 comprises at least one vibrating decoupling pin 20 for fixing the radiator 6 and the printed circuit board 4 (first and third embodiment) or the motor support 3 (second embodiment).

Each pin 20 extends substantially orthogonally to the card 4.

Each pin 20 is made of flexible plastic material and electrically insulating, for example of the SEBS type.

Fixing the radiator 6 or the engine support 3 and the card 4 by the pin (s) 20 stiffens the assembly 1, which allows the assembly 1 to be less sensitive to the vibrations generated by the electric motor.

The flexible material of each pin 20 also contributes to the damping of these vibrations.

In addition, the positioning of each pin 20 allows the optimization of the heat transfer while avoiding electrical contacts. The shape of each peg 20 will be detailed later.

Advantageously, the vibratory decoupling device 10 also comprises a layer 21 of flexible material, preferably electrically insulating, disposed between the motor support 3 and the radiator 6, and preferably overmolded on the motor support 3.

The layer 21 is preferably made of a material made of polymers, such as a flexible PLA or in SEBS.

The layer 21 dissociates the entire card 4 and the radiator 6 fixed to each other of the engine, which helps to reduce vibration.

Note that the offset position of the connector 12 contributes to the reduction of the vibrations which are partly absorbed by the cables of the connector 12.

First embodiment of the pawns

In relation to FIG. 3, the pin 20 according to a first embodiment extends substantially rectilinearly.

The pin 20 comprises a first longitudinal portion 31, a second longitudinal portion 32 and a third longitudinal portion 33, and a first shoulder 34 between the first and second portions 31, 32, a second shoulder 35 between the second and third portions 32 , 33, and a base 36.

The first part forms the gripping rod of the pawn 20.

The length of the second portion 32 is equal to the thickness of the card 4, while the third portion 33 is equal to the thickness of the radiator 6.

In other words, the second portion 32 is shaped to occupy the space of the hole 9 of the card 4 and the third portion 33 to occupy the space of the hole 11 of the radiator 6, the shoulders 35 and 36, and the base 27 blocking these parts in the associated space.

In particular, the base 27 abuts the pin 20.

A thermal paste is optionally added in the holes 9, 11.

Second embodiment of the pawns

In relation to FIG. 4, the pin 20 according to a second embodiment extends substantially rectilinearly.

The peg 20 comprises a first longitudinal portion 41, a second longitudinal portion 42, a shoulder 43 between the first and second portions 41, 42, and a base 44. The first part forms the gripping rod of the pawn 20.

The length of the second portion 42 is equal to the thickness of the motor support 3.

The pin 20 according to this embodiment is intended to fix the motor support 3 and the radiator 6.

Third embodiment of the pawns

In relation to FIG. 5, the pin 20 according to a third embodiment extends substantially rectilinearly.

The pin 20 comprises a first longitudinal portion 51, a second longitudinal portion 52 and a third longitudinal portion 53, and a first shoulder 54 between the first and second portions 51, 52, a second shoulder 55 between the second and third portions 52 , 53, and a base 56.

The first part forms the gripping rod of the pawn 20.

The length of the second portion 52 is in this case equal to the thickness of the card 4 and the ring 13 of the connector 12, while the third portion 53 is equal to the thickness of the radiator 6.

In other words, the second part 52 is shaped to occupy the space of the hole 9 of the card 4 and the hole of the ring 13, and the third part 53 to occupy the space of the hole 11 of the radiator 6, the shoulders 55 and 56, and the base 57 ensuring the blocking of these parts in the associated space.

In particular, the base 57 forms a stop of the pin 20.

The pin according to this embodiment allows the attachment of the connector 12, the radiator 6 and the printed circuit board 4.

Figure 6 illustrates an example of positioning the pins.

In FIG. 6, pins 20-1 and 20-2 make it possible to fix the connector, the card 4 and the radiator 6 while a pin 20-3 enables the card 4 and the radiator 6 to be fixed.

A thermal paste is optionally added in the holes 9, 11.

Manufacturing process

The invention also relates to a method of manufacturing the assembly 1.

The manufacturing method comprises a step of positioning the peg by forced insertion into the orifices intended to receive it, followed by a withdrawal step during which the gripping rod is pulled in one direction. opposite to the direction of introduction so as to position the pin 20, the shoulder or shoulders now blocked the pin in position.

This succession of steps is in particular allowed by the deformation of the flexible pin 20.

Advantageously, the method comprises a preliminary overmoulding step during which the motor support 3 is overmolded with the layer of flexible material 21 and each pin 20.

The radiator 6 and the printed circuit board 4 are then secured to the pin, as indicated above.

Advantages

The pins 20 are a cheaper solution than fixing screws and have the advantage of simultaneously allowing the fixing and reduction of vibrations. In addition, the blocking pin 20 ensures the necessary safety distance between the card 4 and the radiator 6, which prevents any electrical contact. The safety distance is 0.4 mm +/- 0.2 mm.

On the contrary, since a screw is an electrical conductor, care must be taken to avoid short circuits.

Claims

1. An assembly comprising a control module (2) for an electric motor of a motor-fan unit and a motor support (3) for housing said electric motor on which said control module (2) is mounted, the control module (2) comprising a printed circuit board (4) on which electronic components (5) and a radiator (6) in thermal coupling with said printed circuit board (4) are arranged, the assembly (1) comprising a vibrating decoupling device (10) for decoupling the assembly (1) from said electric motor, the vibration decoupling device (10) comprising at least one vibratory decoupling pin (20) for fixing the radiator (6) and the printed circuit board (4) and / or the motor support (3).

2. The assembly of claim 1, wherein said at least one pin (20) is made of flexible plastic material, for example of the SEBS type.

3. Assembly according to one of the preceding claims, wherein said at least one pin (20) comprises a rod (31, 41, 51) for gripping the pin (20).

4. Assembly according to one of the preceding claims, wherein said at least one pin (20) comprises at least one shoulder (34, 35, 36, 43, 44, 54, 55, 56) for locking the pin (20). between the radiator (6) and the printed circuit board (4) and / or the motor support (3).

5. An assembly according to one of the preceding claims, comprising an electrical connector (12) provided with a ring (13), said at least one pin (20) being configured to also fix said ring (13).

6. Assembly according to one of the preceding claims, wherein the radiator (6) comprises a hole (11) for passage of said at least one pin (20) and the printed circuit board (4) comprises a hole (9) of passage of said at least one pin (20), the passage opening of the radiator (11) being arranged opposite the passage opening (9) of the printed circuit board.

7. An assembly according to one of the preceding claims, wherein the vibrating decoupling device (10) comprises a layer of flexible material (21) disposed between the motor support (3) and the radiator (6).

8. A method of manufacturing an assembly comprising a control module (2) for an electric motor of fan motor unit and a motor support (3) for housing said electric motor on which is mounted said control module (2), the control module (2) comprising a printed circuit board (4) on which electronic components (5) and a heat-conducting radiator (6) are arranged with said printed circuit board (4), assembly comprising a vibratory decoupling device (10) for decoupling the assembly (1) from said electric motor, the method comprising a step of positioning at least one vibratory decoupling pin (20) between the radiator (6) and the printed circuit board (4) and / or the motor support (3) so as to fix the radiator (6) and the printed circuit board and / or the motor support (3).

9. Method according to the preceding claim, said at least one pin (20) comprising a gripping rod (31, 41, 51) and at least one locking shoulder (34, 35, 36, 43, 44, 54, 55, 56), the positioning step comprising a step of forcing said at least one pin (20) into the card and into the radiator (6) and / or the motor support (3) and then a withdrawal step during from which is pulled on the gripping rod (31, 41, 51) in a direction opposite to the insertion direction so as to position the pin (20), each shoulder now blocked the pin (20) in position.

10. Method according to one of claims 8 or 9, comprising a molding overmolding step where the pin (20) is directly overmoulded on the motor support (3), the pin (20) being created during this overmolding step .